Recently, a small and light memory card incorporating a semiconductor memory has been developed. A memory card has various sizes. For example, an SD memory card which has been recently developed has a size of a stamp (for example, see Japanese Laid-Open Publication No. 2001-134730).
FIG. 12 shows a structure of a conventional memory card 400. The memory card 400 may be, for example, an SD memory card.
The memory card 400 includes a memory card body 41, a contact terminal 42, and a write enable/disable setting member 50 included in a write protect mechanism.
The memory card body 41 incorporates a printed circuit board and a semiconductor memory. The semiconductor memory is provided on the printed circuit board. On a side surface of the memory card body 41, a notch portion 43 is formed. The notch portion 43 is formed, so that the memory card 400 is prevented from being erroneously inserted into a memory card insertion section of specific type equipment.
In the memory card body 41, a projecting portion 44, step portions 45, a rib portion 46, recessed portion 48, and a notch portion 49 are further formed.
The projecting portion 44 has a width slightly smaller than the memory card body 41 and has a thickness greater than the memory card body 41. The step portions 45 are formed on side surfaces on both sides of the memory card body 41. Each of the step portions 45 has thickness D. The step portions 45 are formed so as to fit onto step portions formed inside a memory card insertion section of specific type equipment. When the memory card 400 is inserted into a memory card insertion section of specific type equipment, the step portions 45 are guided with step portions formed inside a memory card insertion section of specific type equipment. In the rib portion 46, a plurality of projecting portions are formed.
The recessed portion 48 is formed on a side surface on one side of the memory card body 41 enabling it to fit onto a projecting portion formed inside a memory card insertion section of specific type equipment. Since the recessed portion 48 fits onto the projecting portion, the memory card 400 is prevented from being easily detached from the memory card insertion section of the specific type equipment.
The notch portion 49 is formed on a side surface on one side of the memory card body 41. The notch portion 49 is formed on the side surface opposite to the side surface having the recessed portion 48 formed thereon.
The write enable/disable setting member 50 is fitted into the notch portion 49 so as to be slidable with respect to the memory card body 41. The write enable/disable setting member 50 is arranged such that it is selected to be in either the first position or the second position. At the first position, a part of the write enable/disable setting member 50 covers a part of the notch portion 49. At the second position, a part of the write enable/disable setting member 50 covers the other part of the notch portion 49. The write protect mechanism sets whether to enable or disable writing of data into the semiconductor memory in accordance with the position of the write enable/disable setting member 50. The write protect mechanism can mechanically set whether to enable or disable writing of data into the memory card in accordance with the position of the write enable/disable setting member 50. The external shape of the write enable/disable setting member 50 is formed substantially integral to the external shape of the memory card body 41.
The contact terminal 42 is located on the printed circuit board incorporated in the memory card body 41 and electrically connected to the semiconductor memory. The contact terminal 42 is formed so as to be electrically connected to a terminal portion of specific type equipment when the memory card 400 is inserted into a memory card insertion section of the specific type equipment. The contact terminal 42 is exposed to the outside of the memory card 400 from spaces between the plurality of projecting portions formed in the rib portion 46.
Recent enhancement in integration and density of a semiconductor memory enables implementation of a memory card which has a smaller size and a higher capacity compared to the conventional SD memory card and which is adapted for multifunction. For example, a mini SD memory card which is smaller than the conventional SD memory card has been implemented.
In the case where a memory card is miniaturized, compatibility with other memory cards having different shapes becomes a problem. In order to address the problem of compatibility, various adapters have been proposed (see, for example, Japanese Laid-Open Publication Nos. 2000-214970, 2001-297307, and 2001-101356). For example, one type of adapter attaches to a memory card for changing the external shape such that it can be inserted into a memory insertion section of equipment adapted to a conventional SD memory card.
On a side surface of a conventional SD memory card, a write protect mechanism is provided. On a side surface of a SD memory card module including a mini SD memory card and an adapter, a write protect mechanism must also be provided. However, a mini SD memory card should be thin, and should also have a small area. Thus, a write protect mechanism cannot be provided in a mini SD card. If a write protect mechanism is provided in an adapter, there may be a restriction in shape of the memory card to be housed in the adapter body.
The objective of the present invention is to provide an adapter to be attached to a memory card for changing the external shape without electrically setting whether to enable or disable writing of data into the memory card, a memory card structured enabling it to be housed in the adapter, and a memory card module including the memory card and the adapter.